Facet mirror having a number of mirror facets

Abstract

In a facet mirror with a number of mirror facets, wherein the mirror facets are provided with reflecting surfaces, the mirror facets are mounted jointly in a basic body via bearing devices. The mirror facets comprise mirror bodies contacting at the periphery with the bearing devices via a surface, line or point contact. The preferred field of use of the facet mirrors is a projection objective of a projection exposure machine in microlithography for fabricating semiconductor elements.

1. A facet mirror, comprising:
 a basic body of bipartite construction, said basic body having a first plate and a second plate which are displaceable and capable of being fixed relative one another; 
 a number of mirror facets, each of said mirror facets having a mirror body formed with a periphery, a first side and a reflecting surface opposite said first side; 
 a number of bearing devices each extending over both said first and second plates of said basic body, each of said mirror facets being mounted to said basic body so that said periphery of said mirror body thereof contacts one of said bearing devices via surface contact, line contact or point of contact; 
 said mirror facets each being adjustable within one of said bearing devices after which time said first and second plates of said basic body are fixed relative to one another to releasably mount said mirror facets and said bearing devices in said adjusted position. 
 
     
     
       2. The facet mirror as claimed in  claim 1 , wherein an adjusting device is connected to said first side of each of said mirror bodies, said adjusting devices being effective to adjust the position of said reflecting surface of said mirror facets. 
     
     
       3. The facet mirror as claimed in  claim 1 , wherein said basic body consists of a softer material than said mirror body. 
     
     
       4. The facet mirror as claimed in  claim 1 , wherein both of said first and second plates consist of a softer material than said mirror body. 
     
     
       5. The facet mirror as claimed in  claim 1 , wherein said first plate, is situated closer to the reflecting surface of said mirror body and consists of a harder material than the second plate. 
     
     
       6. An adjusting system for a facet mirror having a number of mirror facets each including a mirror body formed with a periphery, a first side and a reflecting surface opposite said first side, said adjusting system comprising:
 a basic body of bipartite construction, said basic body having a first plate and a second plate which are displaceable and capable of being fixed relative one another; 
 a number of bearing devices each extending over both said first and second plates of said basic body, each of said mirror facets being mounted to said basic body so that said periphery of said mirror body thereof contacts one of said bearing devices via surface contact, line contact or point of contact; 
 an adjusting device connected to said first side of said mirror body of each of said mirror facets and an actuator coupled to each of said adjusting devices, each of said actuators each being effective to apply a force to one of said adjusting devices to effect adjustment of the position of a respective mirror body after which time said first and second plates of said basic body are fixed relative to one another to releasably mount said mirror facets and said bearing devices in said adjusted position. 
 
     
     
       7. The adjusting system as claimed in  claim 6 , wherein said basic body consists of softer material than said mirror body. 
     
     
       8. The adjusting system as claimed in  claim 6 , wherein both of said first and second plates consist of a softer material than said mirror body. 
     
     
       9. The adjusting system as claimed in  claim 6 , wherein said first plate is situated closer to said reflecting surface of said mirror body and consists of harder material than said second plate. 
     
     
       10. The adjusting system as claimed in  claim 6 , wherein the adjustment of said mirror facets is performed, under illumination, in the insert of an objective in which the mirror facets are installed.